Q .If the difference between the reciprocal of a positive proper fractionand the fraction itself be 21/14, the fraction is-
Let number be the x -
(1/x ) - ( x/1 ) = 21/14
(1 - x2 )/x = 21/14
14 (1 - x2 ) = 21x
14x2 + 21x - 14 = 0
solve the equation with fast trick method as disccused another video-
so x=1/2 or x=-2/1
So the fraction is 1/2.
